#!/bin/bash /usr/lib/turtle/turtle_module

VERSION="1.0"
DESCRIPTION="Save tcpdump pcap to remote host"
AUTHOR="Dylan Smyth"
CONF=/tmp/turtledump.form

: ${DIALOG_OK=0}
: ${DIALOG_CANCEL=1}
: ${DIALOG_HELP=2}
: ${DIALOG_EXTRA=3}
: ${DIALOG_ITEM_HELP=4}
: ${DIALOG_ESC=255}

function start {
touch /tmp/turtledump.pid
if [ -s /etc/config/turtledump ]
  then
    turtledump_host=$(uci get turtledump.rp_host)
    turtledump_user=$(uci get turtledump.rp_user)
    turtledump_port=$(uci get turtledump.rp_port)
    turtledump_filename=$(uci get turtledump.rp_filename)
    if grep -q $turtledump_host /root/.ssh/known_hosts; then
      echo "Starting Turtledump..."
      echo "(tcpdump -i br-lan -w - not host $turtledump_host | ssh -q -t -p $turtledump_port $turtledump_user@$turtledump_host \"cat >> $turtledump_filename\" &)" | at now 2>/dev/null
      sleep 3 #Give process time to start
      pgrep -f "ssh -q -t -p $turtledump_port $turtledump_user@$turtledump_host" > /tmp/turtledump.pid
      echo "Turtledump started with pid: $(cat /tmp/turtledump.pid)"
    else
      echo "Host $turtledump_host is not known."
      echo "Please use keymanager to generate a key for this host."
    fi
  else
    touch /etc/config/turtledump
    echo "Turtledump is not configured"
fi
}

function stop {
  touch /tmp/turtledump.pid
  if kill -0 $(cat /tmp/turtledump.pid) 2>/dev/null; then
    echo "Stopping Turtledump"
    kill $(cat /tmp/turtledump.pid)
  else
    echo "Turtledump not running"
fi
}

function status {
  if [ -s /tmp/turtledump.pid ]; then
    if kill -0 $(cat /tmp/turtledump.pid) 2>/dev/null; then
      echo "1"
    else
      echo "0"
    fi
  else
    echo "0"
fi
}

function configure {
  if [ -s /etc/config/turtledump ]
  then
    turtledump_host=$(uci get turtledump.rp_host)
    turtledump_user=$(uci get turtledump.rp_user)
    turtledump_port=$(uci get turtledump.rp_port)
    turtledump_filename=$(uci get turtledump.rp_filename)
    
  else
    touch /etc/config/turtledump
    turtledump_port='22'
    turtledump_filename='turtle.pcap'
  fi

  dialog --ok-label "Submit" \
    --help-button \
    --title "Turtledump Configuration" \
    --form "Turtledump\n\n\
Host: IP address of host to establish the SSH connection\n\
User: User to log in as\n\
Port: Port the SSH server is running on (Default 22)\n\
Filename: pcap filename (Default 'turtle.pcap')\n \n" 16 60 4\
    "Host:"      1 1 "$turtledump_host" 1 14 48 0 \
    "User:"      2 1 "$turtledump_user" 2 14 48 0 \
    "Port:"      3 1 "$turtledump_port" 3 14 48 0 \
    "Filename"   4 1 "$turtledump_filename" 4 14 48 0 \
  2>$CONF

  return=$?
  case $return in
    $DIALOG_OK)
      cat $CONF | { 
        read -r turtledump_host
        read -r turtledump_user
        read -r turtledump_port
        read -r turtledump_filename
        touch /etc/config/turtledump
        uci set turtledump.rp_host=$turtledump_host
        uci set turtledump.rp_user=$turtledump_user
        uci set turtledump.rp_port=$turtledump_port
        uci set turtledump.rp_filename=$turtledump_filename      
        uci commit turtledump
        rm $CONF
      };;
    $DIALOG_CANCEL)
      rm $CONF
      clear
      exit;;
    $DIALOG_HELP)
      dialog --title "Help" \
        --msgbox "\
Turtledump will launch tcpdump and write the captured packets to a pcap file on a remost host via an SSH connection.\n\
Use the keymanager module to first create an SSH key for the remote host.\n\
Host: IP address of host to establish the SSH connection\n\
User: User to log in as\n\
Port: Port the SSH server is running on (Default 22)\n\
Filename: Filename for the saved pcap (Default 'turtle.pcap')\n \n
" 20 60
      configure
      ;;
    $DIALOG_ESC)
      clear;;
  esac
}